Method of and apparatus for making packages



Feb. 7, 1939. D. E. MAXFIELD 2,145,941

METHOD OF AND APPARATUS FOR MAKING PACKAGES Filed April 18, 1938 F6925 2Maw w's-zid ATTORNEY.

Patented Feb. 7, 1939 METHOD OF AND APPARATUS FOR MAKING PACKAGES DanielE. Maxfield, Philadelphia, Pa., assignor to Stokes and Smith Company,Summerdale, Pa., a corporation of Pennsylvania Application April 18,1938, Serial No. 202,663

14 Claims.

My invention relates to the manufacture, filling and sealing ofgas-tight packages of flexible web material.

In accordance with my invention, after each package is filled atatmospheric pressure, but before final sealing thereof and detachmentfrom the web material, the air is withdrawn therefrom and, if desired,may be replaced with a suitable conditioning gas.

In accordance with my invention, the margins of one or more webs ofsuitable flexible material, preferably a material which consists of, isimpregnated with, or coated with a thermo-plastic, are joined, as byapplication of heat and pressure, to form a tube which is transverselyflattened at intervals to form a series of containers, and, after eachcontainer is, in turn, filled with its intended contents, and before itsseverance from the webbing, it is flattened above or beyond its contentsto close or seal off the interior thereof except for provisionpermitting its subsequent communication with a vacuum pump or equivalentand thereafter with a source of suitable conditioning gas; afterexhaustion of air from the 5 container and replacement thereof bysuitable gas, the sealing of the container is completed, and it isthereafter severed from the web.

My invention further resides in the methods and systems hereinafterdescribed and claimed.

For an understanding of my invention, reference is to be had to theaccompanying drawing, in which:

Fig. 1 in elevation shows formation of a tube from web material;

Fig. 2 illustrates flattening of the tube of Fig. 1 to form a container;

Fig. 3, partly in section and in part diagrammatic, illustrates a stepof package formation subsequent to Figs. 1 and 2;

Fig. 4, partly in section, illustrates the remaining steps of one methodfor making gas-filled packages;

Figs. 4a and 4b illustrate an alternative method of completing thepackage of Figs. 1 to 3;

Fig. 5 is a plan view in section, taken on line 5--5 of Fig. 3;

Fig. 6 is a detail view, on enlarged scale, of modification of partsappearing in Figs. 1 to 3;

Fig. 7 is a plan view in section of the filling 50 tube construction ofFig. 6.

For the packaging of many products, it is desirable that little or noair or oxygen be permitted to remain in the package for contact with thecontents; moreover, it is often desirable that 55 the air removed fromthe package be replaced by a gas, or gases, having a. beneficial orpreserving effect. The choice of conditioning gas is determined by thenature of the package contents and desired effect upon those contents ofthe conditioning gas.

Although these ends have been accomplished by various methods when thepackage contents to be preserved are in rigid containers such as metalcans, bottles or the like, those methods are not applicable to flexiblepackages or containers during their formation from web material.

In accordance with my invention, these ends are accomplished byinclusion of the steps of exhausting the air ditioning gas as andreplacing it with the conpart of a continuous method withdrawn from aroll R and shaped about a tube l of suitable size to form tubing Thaving longitudinally thereof a seam S which is formed by joinder of theoverlapping margins of the web. Preferably the W consists of, or isimpregnated with, or coated with, a thermo-plastic in ,which case theseam or seal S may be formed simply by pressure of a heated roll LSapplied to press the overlapping web margins against the periphery ofthe forming tube I.

Below the lower open end of the forming tube I the tubing T isflattened, as by application of suitable heated tools, to provide a sealSI extending across the tubing to form the bottom of a container C whoseupper, open end is in communication with the lower open end of theforming tube I; after seal SI has been formed, the intended contents ofthe container, for example, medicinal powders or tablets, tobacco, foodproducts, or the like, may be introduced into the interior thereofthrough the forming tube I.

After the container C has been so filled, it is flattened aboveitscontents, as by the two resilient clamping members 2, 2 (Figs. 4 and5) which cut off communication between the interior of the container andthe filling tube l which is open to atmosphere.

I for communication of the interior of the container with a suitableair-exhaustingapparatus,

such as vacuum pump 6, and with a sourceof conditioning gas I. Whetheror not the members 2, 2 need be relieved or cut away to afford a goodseal at the region adjacent tubes 4, 5 depends inter alia uponthe shapeand size of the tubes. 7

After the clamping tools 2, 2 have moved to the position indicated inFigs. 3 and 5 to efiect a temporary seal, the valve 8 is opened toexhaust the air from the container 0, the contents of the packagepreventing its collapse under atmospheric pressure which throughout themethods.

herein described is always exerted on the exteriors of the packages.When the exhaustion has proceeded to suitable extent, valve 8 in thevacuum line 4 is closed and valve 9 in the gas line 5 is opened topermit a desired vapor or gas, such as nitrogen, carbon dioxide or amixture of gases, from the source I to enter the package. It isdesirable the valves 8 and 9 be located as near as possible to the openends of pipes 6, 5 for minimum cost of vacuum and gas equipment and formost economical operation.

The tubing T forming the upper part of container C may then be flattenedbelow the soft clamps 2, 2, as by heated clamping tools whichpermanently seal the upper end of the container C, thus to complete theformation from web material of a package whose contents are within aprotective gas. The container C becomes an individual container uponseverance of the tubing T above the upper seal.

For continuous production of gas-filled packages, there may be utilizeda machine similar to that disclosed in Zwoyer Patent #1,986,422, orAldrich Patent 1,937,501, suitably modified, to incorporate additionalclamping tools corresponding to the resilient clamping tools 2,2, and toinclude pipes 4,5 and the other necessary auxiliaries herein mentionedfor removal of air from and supply of gas to the containers as they arein turn formed. It is not necessary for performance of the methodsherein described that the supply hoppers or any of the package-formingmechanism be within a vacuum chamber.

Referring to Fig. 4, and in explanation of those steps of one method ofcompleting a package, which steps are subsequent to those of Figs. 1 to3, after. the container 0 has been filled with gas andtbefore separationof the resilient clamping tools 2, 2, the heated clamping tools I0, i0flatten the upper end of the container suitably below the lower ends ofthe pipes 4, 5 thus to complete the sealing of the container C and toprevent ingress of air or other gas upon separation of the clamps 2, 2.The seal formed by the heated clamping tools I0, It comprises thesealing section S2 for the upper end of the container 0 and the sealingsection SI for thebottom of the next container to be filled.

The clamping tools I0, I13 while in engagement with the web or tubing Tare moved downwardly to their dotted line position, Fig. 4, thus tobring the seal SI, S2, between two previously formed containers CI, C2,in position for operation thereon of the knives II, II to detach fromthe web a complete gas-filled package 02, and also to draw more of theweb W from the roll R about the forming tube I for ultimate formation ofsimilar packages.

From the foregoing, it is to be understood that each container, in turn,is formed on tube I, filled with its intended contents, connected insequence ing tools Illa,

to thevacuum ump audio. source of conditioning gas, and thereaftersealed and detached from the webbing. The method, whose final steps areexemplified by Fig. 4, is satisiactory for many kinds of web material,and for many classes of products, but

in some cases, the marking or weakening of the web material at theregions where the clamping tools 2, 2 draw the web tightly around thetubes 4, 5- is objectionable. To avoid this dimculty, there may beutilized the alternative method whose steps, subsequent to the steps ofFigs. 1 to 3, are exemplified in Figs. 4a and 4b. In accordance withthis method, before the resilient clamping tools 2, 2 are moved awayfrom their position oi. Figs. 3 and 5, the top of container C isflattened below tools 2, 2 by the heated clamp- Ifla, which form theseal S2 closing the upper end of the container C; then after'separationof the resilient clamping tools 2, 2, the heated clamping tools Illb,IIlb flatten the tubing T to form the seal SI of the next container; andthis section SI includes those regions where the resilient clampingtools 2, 2 had previously stretched the webbing around the tubes 4, 5.Thus, whether or not the web is weakened by the stretching thereof aboutconduits 4, 5 is of no consequence because those weakened areas arereinforced or healed when joined in the seal SI and, in any event, arenot in such location that if broken through permit escape of gas fromthe package.

While all four tools Illa, Iilb are in engagement with the web, theymove downwardly to the dotted line position, Fig. 4b, to bring thewebbing to such Position that upon operation of the knives II, Ii, eachflattened sealing section between two adjacent containers is divided todetach from the webbing or tubing T a completed gas-filled package whoselower end is sealed by seal SI and the upper end by the seal S2.

The methods herein described are not limited to use of a. single webwhose margins are overlapped, but is equally applicable to other methodsof forming filled packages from one or more webs, such as areexemplified in my copending applications Serial Nos. 183,427 and190,569, filed January 5, 1938 and February 15, 1938, respectively.

As indicated in Figs. 6 and 7, the pipes 4 and 5, for connection of theinterior of the successive containers with a vacuum pump and a source ofconditioning gas, may be threaded into the bottom of forming tube lawhich actually, or in efiect, comprises an outer forming tube aboutwhich the webbing W is formed into tubing T and inner or filling tube I2through which the contents of the packages are introduced, and theannular space between the tubes I a and I2 is divided into two passagesI3 and I4 maintained independent of each other by the barriers I5, I5.The lower end of each of these passages I3 and I4 is closed except foran opening which receives one or the other of the pipes 4, 5. Connectionof the passages I3 and I4, vacuum pump and gas supply is afforded bypipes 4a, 5a which join the tube Ia suitably above the region at whichthe web W is turned around the tube.

The upper end of filling tube I 2 is in communication with a hopper orequivalent source of material for filling of the packages. The hopperand filling tube are at all times in communication with atmosphere andneed not be in a vacuum tank or equivalent for exhaustion of air fromthe successively formed packages.

In any of the modifications shown, if it is not desired to replace theair exhausted from the packages with a conditioning gas, the tube 5 orequivalent may be omitted, plugged, or valve 9 left closed.

What I claim is:

1. The method which comprises forming a receptacle from sheet material,filling and sealing the receptacle to form a gas-tight package, and,between said filling and sealing of the receptacle, and while itsexterior is exposed to atmospheric pressure, withdrawing air therefromby producing a vacuum therein.

2. The method which comprises forming a. receptacle from sheet material,filling the receptacle while its interior is in communication withatmosphere, and thereafter and while the exterior of the receptacle isexposed to atmospheric pressure exhausting air from the receptacle byproduction of a vacuum therein and sealing the receptacle.

3. The method which comprises forming a receptacle from sheet material,filling the receptacle while its interior is in communication withatmosphere, and thereafter, and while the receptacle is exposedexternally to atmospheric pressure, effecting withdrawal of air from thereceptacle to exhaust it, introduction of a conditioning gas into theexhausted receptacle, and sealing of the receptacle.

4. The method of making, filling and sealing packages which comprisesjoining the margins of web material to form a flexible tube, flatteningthe tube transversely to form a receptacle open at one end, filling thereceptacle through said end while its interior is in communication withatmosphere, and thereafter, and while the receptacle is exposed toatmosphere, partially closing said end of the receptacle anddiscontinuing communication of the interior thereof with atmosphere,withdrawing air from the container through said partially closed end,and subsequently sealing said receptacle.

5. The method of making, filling and sealing packages which comprisesjoining the margins of web material to form a flexible tube, flatteningthe tube transversely to form a receptacle open at one end, filling thereceptacle through said end while its interior is in communication withatmosphere, and thereafter, and while the receptacle is exposed toatmosphere, partially clos-' ing said end of the receptacle to interruptcommunication of the interior thereof with atmosphere, withdrawing airfrom the container through said partially closed end, replacing the airwith conditioning gas, and subsequently sealing said receptacle.

6. The method of making, filling and sealing packages which comprisesjoining the margins of Web material to form a flexible tube, flatteningthe tube transversely at spaced intervals to form sealed packages, insuccession filling the packages by introducing material into the tubebetween successively flattened sections thereof, severing the tubetransversely through the flattened sections to detach the packages inturn from the web material, and, after filling of each of the packagesand while it is externally exposed to atmosphere and attached to saidtube of web material exhausting the package interior of gas to effectremoval of air therefrom.

7. The method of making, filling and sealing packages which comprisesjoining the margins of web material to form a flexible tube, flatteningthe tube transversely at spaced intervals to form sealed packages, insuccession filling the packages by introducing material into the tubebetween successively flattened sections thereof, severing the tubetransversely at the flattened sections to detach the packages in turnfrom the tube of web material, and, after filling of each of thepackages and while it is externally exposed to atmosphere and attachedto said tube of web material, producing a vacuum within the packageinterior to exhaust it of air and subsequently introducing aconditioning gas into the exhausted receptacle.

8. A system for forming, filling and sealing packages comprising afilling tube over which tubing of sheet material is'"drawn, means forflattening and transversely sealing the tubing to form a receptaclefilled through said filling tube, a source of vacuum, a hollow memberextending beyond said filling tube and providing for communicationbetween said source and said receptacle, resilient means for flatteningthe tubing about said member to prevent communication of the interior ofsaid receptacle with atmosphere and to permit withdrawal of airtherefrom, and means for transversely flattening and sealing the tubingbetween the filling material of said receptacle and said resilientmeans.

9. A system for forming, filling and sealing packages comprising afilling tube over which tubing of sheet material is drawn, means forfiattening and transversely sealing the tubing to complete closure of afilled package and to close one end of a receptacle to be filled throughsaid tube, a source of vacuum, a hollow member extending beyond saidfilling tube and providing for communication between said source andsaid receptacle, and resilient means for flattening the tubing aboutsaid member, after filling of said receptacle and in advance of completeclosure and sealing thereof by said first means, to preventcommunication of the interior of said receptacle with atmosphere and topermit withdrawal of air therefrom.

10. A system for forming, filling and sealing packages comprising afilling tube over which is drawn tubing of sheet material, a source ofvacuum, a hollow member extending beyond said fill ing tube andproviding for communication between said source and the interiors of thesuccessive packages after filling thereof, resilient temporary-sealingmeans for flattening the tubing and clamping it about said member toisolate the interior of a filled package from atmosphere and to permitwithdrawal of air therefrom, and means for transversely sealing thetubing between the contents of each package and said temporarysealingmeans before disengagement of the latter from the tubing.

11. A system for forming, filling and sealing packages comprising afilling tube over which is drawn tubing of sheet material, a source ofvacuum, a hollow member extending beyond said filling tube and providingfor communication between said source and the interiors of thesuccessive packages after filling thereof, resilient temporary-sealingmeans for flattening the tubing and clamping it about said member toisolate the interior of a filled package from atmosphere and to permitwithdrawal of air therefrom, and means for transversely sealing thetubing between the contents of each package and said temporarysealingmeans before disengagement of the latter from the tubing and forthereafter transversely sealing the tubing at a region previouslyclamped by said temporary-sealing means.

12. A system for forming, filling and sealing uum, a source oiconditioning gas, hollow struc ture extending beyond said filling tubeproviding} for connection to said' sources 'of the interiors of packagesin succession formed from said tubing, resilient temporary-sealing meansfor flattening the tubing and clamping it about said structure duringconnection of the interior of a filled package with said sources, andmeans for transversely flattening and permanently sealing the tubingbetween the, contents of each package and said temporary-sealing. meansbefore disengagement ofthe latter from said tubing.

13. The method which comprises forming a. receptacle from sheetmaterial, filling the receptacle while its interior and exterior areexposed to atmospheric pressure, thereafter reducing the Patent no.2,115,914; a

requiring correction as follows a structure against the "sealing-thereceptacle to retain I go mrrmcsra on connection in a; j It is herebycertified that'erronappears;

pressure interiorly of the filled receptacle to exhaust air therefromwhile its filling supports its wall structure against the external amospheric pressure, and thereafter sealing the exhausted receptacle. i

14. The method which comprises forming a receptacle from sheet material,filling the receptacle 7 while its interior and exterior are exposed toat-,

mospheric pressure, thereafter reducing the pressure interiorly of thefilled receptacle to exhaust air thereiromwhile its filling supports itswell external atmospheric pressure, thereafter introducing aconditioning gas into the exhausted receptacle, and thereafter gas and.the filling protected thereby.

DANEL E.

' February ,7', 1959.

the conditioning 15 above number-ed patent In the grant, iline 2, and inthe heading.

to the printed specification, address of aesignee,after 'simnnerdale,"in- ,aert --Phi1adolphia,-:- aa shown by thereco'r d of jaejeiignmentein this office;

page I, second column,

' line 38, strike out the-comma after mm, line 69, claim 6, after"naterial if' line fifi ron 'id" read =15 wf pege 2, first column,

"Fniodified" page 5 first col.- in'af or'ta-comna; and-that the saidLetters ratent'ehould barbed with thiecorrection therein that the-samemay confer-into the record oi the caeeindiie patent office.

signed andjealod this 111:1; def or m s-ti, A-*.n. i9l 1{ 7 (Seal),

'i P Disclai ner" lienr y Van Arsdale,

1 'COllillliBBiOltlZf of Patents.

' 45 34 I D n e a. was, l phi Pa; ,liie'thod ofhnd apparatus for Herebydisclaims iroin the subject and scope ofeachyoi. claim 1, 2;, 3,1,, 5,13 ,and ll,

of said specific ration,

those'methods which are not, Y I

characterized by the-ifact'the exhaustionfofthe vreceptacle"orflcontainer, while" exposed to atmosphere,

isjefi ected prior to detachment thereof or sheet material from iro nthe web mien fO rm6d.,

I G z te, a n

